Machine for concentrating ore



March 26, 1935. e. s. NELSON MACHINE FOR CONCENTRATING ORE 2 sheets sheet 1 Filed Jan. 12, 1932 March 26, 1935.

G. s. NELSON 3,995,433

MACHINE FOR CONCENTRATING ORE Filed Jan. 12, 1952 2 Sheets-Sheet 2 I N VEN TOR Patented Mar. 26, 1935 PATENT OFFICE 7 1,995,433 M HI E OR C E TF HNG R G or S- N on, l La e City, ah

Application January 12,

11 Claims.

My invention relates to improvements in a machine 'for concentrating ore in which the concentrate is separated from the Waste material by a mechanical process.

Among the objects of my invention are the following; 1) To provide a machine that willseparate metals from the waste materials in which they occur by taking advantage of the difierence inthe specifio'gravities and'the diiferences in the sizes of the crushed particles of the different materials. (2) To .provide a machine that may be motivated by any ordinary source of power. (3) "To provide a machine that will operate effectively with air as'the only medium used in the process of separating concentrate from waste. (4) To providea machine that will automatically regulate itself to work at'its highest efficiency, regardless of the sizes of. the particles of material fed to it. (5) To'provide amachine that will carry the waste material to the place of disposal and that will carry'the concentrate to containers without giving the workmen access to .the concentrate while it is in transit.

There are certain ores capable of separation from their .waste by mechanical means, and much of this work is being done at thepr'eserit" time by the flotation process, or by machinessuch as jig tables. These methods howe.ver,'require a large quantity of equipment, because their action is slow. Furthermore, these machines require 'the use of large quantities of water which often is not available at the mine. There is therefore need for a small machine that will do'the 'work of several machines of the types now in use.

Often considerable expense can be avoided if the ore can be concentrated at the mine, thereby making it necessary to .pay shipping charges on the concentrate only, and saving .the enormous cost of shipping waste material.

The ore concentrator of my invention requires be adapted to use any type of power available.

My invention should therefore be the means of placing many mines having low grade ores on a working basis, and should save ,the richer mines from enormous freight expenses.

In general, the machine of my invention, owes its ability to separate concentrate from Waste to the fact that it first disposes the particles of crushedmaterial into separate .piles, in'each of which piles all of the particles of concentrate will beapprogrirnately of the same sizeand relatively 1932, Serial n 586,144 (01. 209-4 small, while'all the particles of waste in any pile will'be approximately the same. size as one another but larger than'thepar'ticles of concentrjate the same pile; and secondly, utilizes the distinct diiferences 'in size and specific'gravity of the particles in each one of the classified p les offmaterial to thoroughly Separate the concentrate from the waste.

The workings ,of'the machine and the'manner of attaining the objects of 'my invention will be made'more apparent by theaccompanying drawings and the renewin specification.

In the drawings, Fig.1 is a side view of the machine for concentrating ore. Fig- .2 is, an en larged part cross section .thru Fig. 1; Fig; 3 is a longitudinal section thru one side of the machine, taken just outside of pivot 10 '(see'Fig. 3)flooking toward fluid passage 6. Figure 4 is a jlongitudie nal section thru an alternate type of machine that uses scre nsinsteadof [p n Similar numerals refer. to the several views.-' V

' After the ore from the mine has been crushed sufliciently fine to loosen the concentratefrom the Waste it is carried by belt 1 to screen .2. Screen 2 .is caused'to vibrate by eccentric 3. Material toocoarse ,for'fseparation is carried by screen 2 totrough A: which returns it"tothe crusher; while properly crushed material I is passed by screen? and guided by funnel 5 into fluid passage 6. Fluid. passage 6 is bounded by casing 11.' Motor '7, or its equivalent, motivates pump 8 which supplies a current of fluid to passage fi. Motor 7' also vibratespans 9 and gates 16 by r'neansof motor shaft52 to which cog wheel 53 is keyed. Wheel 53 meshes with cog wheel 54 which turns shaft 55. Shaft 55 motivates one'or more eccentrics as illustrated in Figure 2, the'collar 56 of the eccentricibeing attached to the still longitudinal member 12 which in turn is attached topans 9. The bearings for shaft 55 are' preferably attached to a longitudinal frame member 5'7 which in turn is supported by legs 32. Fluid passage 6 increases in cross sectional area toward the farther end from the ore feed, consequently .the 'fiuid'velocity in the fluid pas- "similar parts lthruout sage decreasesas it approaches vthe'farther end.

When particles of different sizes and specific gravities are injected into the air stream the heavier particles will fall in approximately the same place as lighter particles having (ll/d2 times the volume of the heavier particles,-where d1 is the specific gravity of the heavier particles and d2 that of the lighter ones.

The larger particles of material carried into passage 6 will be the first to drop to pans 9 but the velocity of the current will be regulated by means such as a, variable speed motor to drop practically all of the material before it reaches the outlet end of the passage. At spaced intervals pans 9 are equipped with ribs 15 to direct the crushed particles down the sloping sides of pans 9 and onto gates 16, and to prevent'loss of material thru the spaces between thegates, and to prevent forward or backward movement'along passage 6. Pans 9, gates 16, and aprons 14 are preferablyattached together so as to vibrate in particles of waste the sameidistance along passagef6 as it will carry smaller, heavier particles of concentrate; v

'Ihe'vibrating motion ofv pans 9 and gates 16 will cause the smaller, heavier particles of waste, represented by the dots in Fig. 2, to settle to the bottom, and the larger, lighter particles of waste, represented by crosses in Fig. 2, to work to the top. By the time the material reaches the front edge of apron 14 it will be separated into an upper layer of waste and a lower layer of concentrate. i

Each gate 16 is provided with a counterweight 20 and a pivot 10. Each counterweight is preferably provided with a screw 21 to adjust the balancing effect of the counterweight so as to hold gate 16 closed against apron 14;when gate 16 is covered entirely with waste to a height a little above edge 22 such as 19, .but so as to allow gate 16 to open when covered with concentrate to a height up to edge 22, or with concentrate upto some point such as .18 plus waste up to a point such as 19. This'will cause'the waste to always discharge ,over edge 22 and never past edge 17. The heavier concentrate will always discharge past edges 17 and willnot flow over edges 22. This causes the concentrate 'toflow into chambers 23 and the waste into chambers 24.

Preferably set screws 25 and 26 will be used to regulate and properly restrict the motion of gates 16.

The concentrate and waste are carried to their places of disposal by belts 27 and 28 respectively. The belts may be supported by rollers 29. Passage 23 may easily be made inaccessible to workmen or others by casings 30 and 31,

Clearly, without the segregating'work of passage 6, a jumbled mixture of particles of both waste and concentrate of all sizes would fall in one heap. V In this case pans 9 and gates 16 could not separate waste from concentrate efficiently because the lower layer of material would then I consist of small particles of concentrate and Waste, while many large particles of concentrate would ride in the upper layer above the small particles of waste. In this event some large particles of concentrate would be discarded with the waste, and some small particles of waste would be carried away with the concentrate.

The velocity of the fluid current in passage 6 may be regulated automatically to drop most of the material at the center of the fluid passage 6 and practically none of the material at the ends, thus assuring the most efiicient working of the machine. This may be. accomplished by two pieces of apparatus set in the opposite ends of air passage 6. When material accumulates on the apparatus in the outlet end, the motor and the fluid current, will be automatically slackened in speed, whereas an accumulation of material at the narrow end will cause the fluid velocity to increase.

The fluid expelled from the larger end of passage 6 may be directed thru a passage, not shown in the drawings, back to the pump intake, thereby causing it to be used over and over again. In this way pollution of the atmosphere by small floating dust particles injurious to the lungs, may be'prevented.

These small particles may be used along with the fluid in the machine Without hampering its operation. From time to time these particles may be filtered out if this is found to be necessary or desirable.

Under some conditions it may be desirable to submerge gates 16 in water, bringing the water level approximately upto the lower edges of pans 9. This may bring about more rapid and more thorough segregation of waste and concentrate than the action of air alone. Either a liquid or a gas maybe used exclusively, as desired, as the materials will be segregated by the same principle in either medium.

It is worthy of note that this machine will work eificiently regardless of how fine the material is crushed.

The machine may be supported on a base 33 by legs 32.

To summarize, my machine for concentrating ore causes bra that has been'sufliciently crushed to loosen the concentrate from the waste material, to be distributed along the surfaces of pans so that uniformly sized particles of concentrate will fall in the same locality as larger uniformly sized particles of waste. This combination of materials is then vibrated until the concentrate forms a bottomlayer,andthe wasterides above. These layers pass onto a series of counterweighted gates that pass the concentrate onto theft-proof carrier belts, and that cause the waste to overflow onto carrier belts that dispose of this material.

As an alternate, screens may be substituted for pans 9 and gates 16, the mesh of these screens being graduatedso as'to have the largest mesh under the small end of the fluid passage and the smallest mesh under the outlet end. The fluid current would then have to be so regulated, and the screens so arranged that the concentrate would be passed and the waste retained by the screens. 7 V

The action of the aforementioned alternate arrangement is more particularly shown and explained by Figure 4 of the, drawings and the following description.

The particles of material are fed to the alternate machine the same as in the machine described above, and this material will be distributed along the bottom of passage 6 in a similar way to that described above. Large particles of waste and smaller particles of metal will drop together at the small end of the passage, and smaller particles of waste along with relatively smaller particles of metal will drop together'at the outlet end of the passage. These smaller particles will be directed by pan 41 down on to-a fine screen 35. Still larger particles of waste and metal will fall on pan 42 and will be directed to passage 43, and so forth until the largest particles of waste and metal are deposited on passage '46. Pan 51 illustrates a typical way of reinforcing and stiffening the upper edges of screens such as'36.

The sizes of the openings at the upper ends of passages43 to 46 inclusive may be regulated to catch all of the material and direct it'to the proper sized screen. 5

The mesh of screens 35 to 39 vary in size, screens- 35 having the finest mesh and each succeeding screen having larger mesh than the preceding onezy Passage 6 is preferably providedwith' a flexible joint '48 so as to permit the'lower portion of the machine to vibrate free from passage 6 and blower 8; I v

The screens and gates (when gates are used) are vibrated by means of eccentric mechanism powered by means such as motor 7, Cog wheel 61 is turned by shaft 55, and meshes witl'i'cog wheel 62, Wheel 62 turns shaft 63 to which'th'e discs of one or morefeccent'rics arekeyed. The collar, or collars, 56 of these eccentrics are ref: erably attached to pan 40, and the bearings for shaft 63 are attached to the rigid member 64 of the frame which in turn is supported by legs 32. Screens 35 to 39 inclusive are preferably attached to side walls 66 whichin turn are closed off at their two ends by pans 40 and 50. Links 60 are preferably attached to pans 50 and to the frame 3Bp 'y pins 53 and59 respectively, thereby permitting the screens to vibrate.

The flow of the air stream will be regulated to deposit wastematerial on the successive screens in such sizes that said material will not pass said screens, but at the same time said fluid stream will deposit metalparticles on the screens of such size that the metal will pass, excepting some of theflaky particles. J

Clearly the small particles that pass screen 35 will also pass the remaining screens, and the metal particles fed to screen 36 will pass screens 37, 38, and 39 so that eventually the metal will all pass to pan 40 and thence down passage 47 to outlet 49. If gates 16 are omitted the waste material will pass out at the lower ends of the screens.

Usually in placer deposits there is some flat or flaky gold and to recover this material, gates '16 may be used to advantage at .thelower edges of the screens as shown in Figure 4. This flaky material, that will not pass the screens, will pass thru the slot between gates l6 and aprons 14; The size .of this slot may be regulated by means of set screws 25 and 26 (or similar means) so that the larger particles of waste material will not pass and the smaller and thinner particles of metal failing to pass the screens, will pass thru the slots. 7

The vibratory motion-of the gates and aprons will cause the openings between the gates and aprons to vary between the limits controlled by means such as set screws 25 and 26. This rapid variation in the openings will prevent material from lodging therein.

The metal passing under apron, or barrier, 14

expensiva'and thorough ore concentrator,w.ell

adapted for use either at the mines or at centralized mills. V

The machine shown in the drawings illustrates one form of the invention but it is not my intene tion to limit my invention to the specific form disclosed.

Having thus described .my invention what :I now claim as new and desire to secure by Letters Patent of theUnited States is as follows:

i 1. In a machine for concentrating ore, a

smooth-'fluidpassage-way having a constantly increasing cross sectional area from one end'to the other, means forsuppIying a fluid current to the passage, means for injecting crushed ore into the fluid current, sloping pans disposed below the fluid passage whereby a bottom side for the fluid passage is formed, a series of gates disposed at the outer edges of the pans, counterweights for the gates whereby thecarrying capacity of the gates may be regulated, aprons disposed just above the outeredges of'the gates and against which the gates may close, means for vibratingthe pans, gates, counterweights, and aprons in unison, a passage disposed just below each apron, said passagebeing divided by a partition disposed directly under the aprons, whereby the concentrateinight be kept separate'from the waste, a series of ribs whereby the pans are divided into ,a series of compartments, and whereby the pans are joinedto the aprons, and whereby the side spaces between the gates are covered 2. In a machine for concentrating ore, a smooth fluid passage-way, means disposed at the inlet eridthereof thru which small particles of material may be injected into the fluid stream, pans disposed below the passage, said pans being slight- 1y inclined, gates disposed at the lower edges of the pans, means for vibrating the gates and pans whereby the small particles of material will be worked to the bottom and large particles to the top of the shallow stream of material caused to flowslowly down the pans, adjustable counterweights for the gates whereby said gates will be closed when they are covered entirely with waste material and whereby they will be allowed to open when covered to a shallow depth with metal,

shallow barriers against which the gates may be closed and over which the uppermost material on the gates may flow, each of said barriers having enough depth to withhold a quantity of metal with weight sufiicient to open said gates before allowing any metal to flow over the barrier.

"3. In amachine for concentrating ore, a smooth fluid passage-way, meansdisposed at the inlet end thereof thru which the small particles of material maybe injectedinto the fluid stream, bottom screens disposed below the passage, said screens being slightly inclined, gates disposed at the lower edges of the screens, means for vibrating the gates and screens whereby the small particles of material will be worked to the bottom and large particles to the top of the shallow stream of material caused to flowslowly'down the screens, adjustable counterweights for the gates whereby said gates will be closed when they are against which the gates may be closed and over which the uppermost material on the gates may flow, each of saidbarriers having enough depth towithhold a quantity of metal having weight suiflcient to open said gates before allowing any metal to flow over the barrier.

4. A machine comprising a fluid passage bounded on its two sides and top by smooth walls wherebya fluid stream will be directed along a smooth course, an inclined top side for the passage whereby the cross sectional area of the passage is increased as it approaches the outlet end of said passage, means for forcing a fluid current thru the passage, means for injecting small particles of material into the fluid stream near the small end of the passage, inclined pans disposed below the fluid passage, gates disposed at the lower edges of the pans, shallow barriers disposed above the lower edges of the gates, means for regulating between certain desired limits the sizes of the openings between the gates and the barriers, andmeans for vibrating the bottom pans and gates. 5. A machine comprising afluid passage bounded on its two sides and top by smoothwalls whereby a fluid stream will be directed along a smooth coursejan inclined top side for the passage whereby the cross sectional area of the passage is increased as it approaches the outlet end of-the passage, means for forcing a fluid current thru the passage, means for injecting small particles of material into the fluid stream near the small end of the passage, inclined'screens disposed below the fluid passage, gates disposed at the lower edges of the screens, shallow-barriers disposed above the lower edges of the gates, means for regulating between certain desired limits the sizes of the openings between the gates and the barriers, and means for vibrating the screens and gates.

6. A machine comprising a fluid passage bounded on its two sides and top by smooth walls whereby a fluid stream will be directed along a smooth course, an inclined top side for the passage whereby the cross sectional area of the passage is increased as it approaches the outlet end of the passage, means for forcing a fluid current thru the passage, means for injecting small particles of materialinto the fluid stream near the small end of the passage, inclined screens disposed below the fluid passage in such relation that a series of outlets for material will be formed in the bottom of the fluid passage and a series of substantially parallel passages will be formed between the screens, each succeeding screen having closer, mesh than the preceding one as said screens approach the outlet end of the fluid passage, gates disposed at the lower edges of the screens, shallow barriers disposed above the lower edges of the gates, means for opening and closing the gates, means for regulating between certain desired limits the sizes of openings between the gates and thebarrieIS, and means for vibrat ing the screens and gates.

'7. A machine comprising a fluid passage bounded on its two sides and top by smooth walls whereby a fluid stream will be directed along a smooth course, an inclined top side for the passage whereby the cross sectional area of the passage is increased as it approaches the outlet end of the passage, means for forcing a fluid current thru the passage, means for injecting small particles of material into the fluid stream near the small end of the passage, inclined screens. disposed below the fluid passage in such relation that a series of outlets for material will be formed in the bottom of the fluid passage and a series of substantially parallel passages will be formed between the screens, each succeeding screen having closer mesh than the preceding one as said screens approach the outlet end of the fluid passage, and means for vibrating the screens.

8. A machine having a fluid passage, an aperture disposed at the inlet end thereof thru which small particles of material may be injected into the fluid stream, bottom screens disposed below the passage, gates disposed at the lower edges of the screens, shallow aprons against which the gates may close and over which the uppermost material on the gates may flow, means for restricting the sizeof the opening between each gate and apron between certain limits, and means for effecting a rapid pulsatory variation in the opening between each of the gates and aprons.

. 9. A machine having a fluid passage, an aperture disposed at the inlet end thereof thru which small particles of material maybe injected into the fluidstream, bottom pans disposed below the passage, a series of gates disposed at the lower edges of. the pans, adjustable counterweights for thegat-es, and shallow aprons against which the gates may close and over which the uppermost material on the gates may flow and means for efiecting rapid pulsatory variation in the opening betweeneach of the gates .and aprons.

10 A machine comprising a smooth fluid passage-way whereby a fluid stream will be directed along a smooth course, an inclined top side for the passage whereby the cross sectional area of the passage is increased as it approaches the outlet end of the passage,.means for forcing a. fluid current thru the passage, means for injecting small particles of material into the fluid stream near the small end of the passage, inclined partitions disposed below the fluid passage in such relation that a series of outlets for material will be formed in the bottom of the fluid passage and a series of substantially parallel passages will be formed by the partitions, and separating means disposed in each of said substantially parallel passages whereby particles having a low specific gravity may be separated from smaller particles having a higher specific gravity.

11. A machine comprising a smooth fluid passage-way whereby a fluid stream will be directed along a smooth course, an inclined top side for the'passage whereby the cross sectional area of the passage is increased as it approaches the outlet end of the passage, means for forcing a fluid current thru the passage, means for injecting small particles of material into the fluid stream near the small end of the passage, inclined partitions disposed below thefluid passage in such relation that a series of outlets for material will be formed in the bottom of the fluid passage and a series of substantially parallel passages will be formed by the partitions, and separating means in each of said substantially parallel passages whereby the larger particles may be separated from the smaller particles disposed therein.

' GEORGE S. NELSON. 

